Underwater electrical connector

ABSTRACT

A plug and receptacle for connecting electrical circuits under water, consisting of two mating chambers filled with a dielectric fluid sealed to prevent loss of fluid but having a resilient liquid-tight interface with the surrounding water so that the pressure within the chambers is equalized with the external pressure. Each of the chambers contains a pair of rods which move in opposed synchronized parallel movement such that one rod moves out of one chamber across the boundary and into the second chamber while the second rod is retracted into the chamber. As each rod moves across the boundary, its movement is accompanied by an equal and opposite movement of its counterpart rod in the other chamber. This synchronized seesaw movement results in a zero volume change in each of the chambers. The rods in their transferred position conduct electrical currents from one chamber to the other.

[11] 3,821,690 June 28, 1974 UNDERWATER ELECTRICAL CONNECTOR Frederick B. Small, Syracuse, NY.

[73] Assignee: Crouse-Hinds Company, Syracuse,

[22] Filed: Feb. 5, 1973 [21] Appl. No.: 329,478

[75] Inventor:

8/1970 Robinson 339/94 M 6/l96l Wofford 339/75 R Primary Examiner-Richard E. Moore Attorney, Agent, or Firm-Robert E. Sandt [5 7] ABSTRACT A plug and receptacle for connecting electrical circuits under water, consisting of two mating chambers filled with a dielectric fluid sealed to prevent loss of fluid but having a resilient liquid-tight interface with the surrounding water so that the pressure within the chambers is equalized with the extemal pressure. Each of the chambers contains a pair of rods which move in opposed synchronized parallel movement such that one rod moves out of one chamber across the boundary and into the second chamber while the second rod is retracted into the chamber. As each rod moves across the boundary, its movement is accompanied by an equal and opposite movement of its counterpart rod in the other chamber. This synchronized seesaw movement results in a zero volume change in each of the chambers. The rods in their transferred position conduct electrical currents from one chamber to the other.

6 Claims, 7 Drawing Figures dmw 00 mm awn 3 R H ow ml 1 1 1 dww 9% Nb i E8 3 F W hw 0 mm 2 mm WI E W S m A don mw 0m mm 6% 5 WWW M v x Am," 1 v m ii I 1 I ium |1 M a. \K 2 f 05 M /M 1 6 U n HI P P HH III I 1 l I E I Tl now 6mm O d A nm Om mo D... now uw dam Ow fim 000 m, 6mm, nwh wh I UNDERWATER ELECTRICAL CONNECTOR BACKGROUND OF THE INVENTION DESCRIPTION OF THE PRIOR ART Connectors for use under water have been one of several types, one of which is not truly an underwater connector. This particular type employs an inverted bell filled with air and containing the receptacle. The plug enters the air chamber and is mated with the receptacle in an air atmosphere.

A second type of plug employs a more or less conventional pin and sleeve plug and receptacle with tightfitting resilient dielectric members which seal the connector against the entrance of seawater in the connected position. The plug and receptacle, including the contact members, are exposed to seawater in the detached position. The sleeves in the receptacle are open to the sea at both ends so that when the pin is inserted into the sleeve the seawater is expelled through a port.

A third known device seeks to overcome the disadvantage of the other types by employing seals and be]- lows to absorb the volumetric change as the plug is inserted.

SUMMARY OF THE INVENTION DESCRIPTION OF THE DRAWINGS F IG.1A is a schematic drawing illustrating the principle of the invention and showing the apparatus in the electrically disconnected position.

FIG. 1B is a schematic drawing showing the apparatus in the electrically conducting position.

FIG. 2 is a longitudinal cross-sectional view of the preferred embodiment.

FIG. 3 is a transverse section taken at 3-3 in FIG. 2.

FIG. 4 is an exploded isometric view showing the operating shaft seal.

FIGS. 5A and'SB are isometric views of the contact rods and operating mechanism in the electrically disconnected and connected positions respectively.

DESCRIPTION OF THE PREFERRED EMBODIMENT Before describing the preferred embodiment it is well to digress and examine the principle of the invention. For this purpose reference is made to the simplified schematic drawings of FIGS. 1A and 1B.

Because of the liberties taken to provide a schematic showing no attempt will be made to correlate the schematic components with the corresponding actual components in the preferred embodiments through use of similar or corresponding reference characters.

Since the plug and receptacle are substantially identical in structure the same reference numerals will be used for corresponding parts in both units with the addition of an a and b suffix to denote left or right. Whether a unit is a plug or a receptacle depends on which is connected to the source of power and which to the power-receiving device.

In FIGS. 1A and 18, a and 10b represent rigid structural housings which are filled with a dielectric fluid (not shown). Flexible diaphragms 12a and 12b provide a flexible interface between the fluid in the chambers and the surrounding seawater to prevent intermixing and to permit minor volumetric changes occasioned, for example, by the compressibility of the dielectric fluid or other materials, or by thermal changes.

The plug and receptacle are shown abutting (mated position) in both figures. In FIG. IA there is no electrical conduction. The rods 14a, I601, and 14b and 16b lie completely within their respective chambers. Nothing crosses the interface 18 common between the plug and receptacle.

Rods 14a and 1l4b are fabricated of insulating material and have integral contact members 20a, 22a and 20b and 22b respectively. To each of these contacts is connected an individual flexible wire 24a, 26a. 24band 26b, which pass through watertight seals 28a and 28b.

Other wire pairs 30a, 32a and 30b and 32b pass through similar watertight seals 3 4a and 34b and are connected respectively to movable contact members 36a, 38a, 36b and 38b.

The rods 16a and 16b are dummy rods fabricated of insulating material. Their functions are to occupy volume within the chambers and provide closure for the contact entrance ports in the off position. All rods are provided with seals (not shown) in the housing to prevent fluid leakage. I

If it is assumed that power is deliverable from left to right, the potentials on wires 24a and 26a connecting to contacts 20a and 22a respectively have no further connection and consequently no outlet. Similarly, the potentials on wires 30a and 32a have no connection be yond movable contacts 36a and 3830. By analogy in the right half there is no electrical continuity between the rods and the movable contacts.

When the rods are moved in seesaw fashion to the position as shown in FIG. 1B no change in volume oc ours in either chamber and electrical conductivity is established. Rod 14a moves to the left across the interface 18 and into the right chamber. Rod 16b retracts into the chamber by an equal distance. This movement would result in an increase in the volume of the left chamber and a decrease in the right chamber but for an equal and opposite movement of rods 16a and 14b resulting in a zero volume change. Derivatively, all rods have the identical cross-sectional area and are moved in syncronism by mechanism to be described with respect to the preferred embodiment.

In the position of the parts shown in FIG. 18 power now flows from wire 24a, contact 20a, movable contact 38b (now engaged) to wire 32b. A second circuit flows from wire 26a, contact 22a, contact 36b (now engaged) to wire 30b. A third circuit is established from wire 30a, contact 36a, contact 22b, to wire 26b. A final circuit exists from wire 32a, contact 38a, contact 20b and wire 24b. Obviously, the roles of the units could be reversed.

In summary, the mating housings are filled with dielectric fluid and contain like pairs of axially translatable rods which are normally flush with and contained within the housings in fluid-tight seals. When connected for delivering power, one of each of the two pairs of rods moves across the interface between the housings while the second rod of each pair retracts into the housing to maintain a constant volume. Each of the rods which advances across interface carries current from its mother housing to the receiving housing.

Turning now to the actual embodiment for perfecting the functions hereinabove described with reference to the schematic showings, reference is made to FIGS. 2 through 58. These figures depict a four circuit plug and receptacle of substantially identical construction, with but one exception. The left unit in FIG. 2 has an external handle for manual manipulation to move the rods in the seesaw movement. Other than this and the attendant seals and shafts, the left and right hand units are identical. Therefore, only the left unit will be described so as to eliminate unnecessary duplication. The a and b suffixes will be employed as before. If a component is unique to one unit only it will have no letter suffix.

Referring now to FIG. 2 a rigid housing 50a provides abrasion resistance and protects the interior parts against mechanical damage. It is provided with apertures so that it cannot not seal the interior parts against the entrance of seawater. Mounted within the housing 50a is a skeletal framework or spine 52a in a close fit. This spine has enlarged cylindrical end sections 53a and 54b which have a sliding fit with the housing 50a. For a distance inboard of these end portions the spine is cylindrical in cross section but of a lesser diameter. A generally cylindrical flexible thin wall bladder 55a is cemented to these reduced cylindrical portions just inboard of the shoulders of the end sections 53a and 54b. The spine 52a is affixed to the housing 50a by screws (not shown) which enter the end portion 53a from the housing.

Further inboard of the reduced cylindrical sections the spine 52a is cut away to provide two parallel flat surfaces as is best seen in FIG. 3. This is done both to provide a reasonable volume of empty space to be filled with the dielectric fluid and to provide clearance for the operating mechanisms. Two parallel bores are drilled longitudinally in spine 52a with their centerlines disposed at opposite ends of a diameter of the circular end sections and equidistant from the center. These bores have reduced sections 59a and 60a to the rear and larger diameter sections 61a and 62a toward the front. These are bored in the noncutaway portion of the spine 52a as shown in FIG. 3 where only a portion of the bores 59a and 60a are shown because of additional cutouts. Sliding within each of these bores is a rack 63a attached to a rod 64a (in bore 59a) and rack 65a attached to rod 66a (in bore 60a). The racks 63a and 65 a mesh with a pinion 67a such that the rack 63a lies to the leftmost position of its stroke and rack 65a to the right. Rotation of gear 67a causes the racks with their attached rods to move in opposite directions with equal synchronized strokes.

The rod 64a is an active rod, in that it conducts current, and is longer than rod 66a, which is a dummy rod. Rod 64a must when operated move into the right chamber and coact with the contact elements therein. Both rods 64a and 66a are flush with the front surface of the plug in the electrical disconnect state.

The gear 67a, as shown in FIG. 3, is mounted on a stub shaft 68a journalled in a bushing 69a pressed into spine 52a and in a second bushing 70a pressed into a shouldered plug 7111 which is pressed into a complementary bore in spine 52a. This arrangement permits insertion of the gear and shaft, the plug 71a being larger than the major diameter of the gear.

An O-ring 72 in plug 7 la seals shaft 68a against passage of fluid. A circular plate 73 screwed to plug 71a compresses and retains the O-ring. A second circular plate 74 is screwed to plate 73 and compresses the bladder 55a between the plates to provide a fluid-tight seal. A forked coupling 75 engages with a pin on gear shaft 68a to provide rotational coupling therewith. Coupling 75 is pinned to the operating handle 76. A plate 77 is fastened to housing 50a and fits between coupling 75 and handle 76 to journal the assembly and restrict its axial movement. The operating mechanism is shown in section in FIG. 3 and as an exploded isometric in FIG. 4.

Since only one of the connector halves has an operating handle, no shaft seal and no bladder seal are required for the right unit. Since the right unit has no shaft seal none of the parts 72, 73, 74, 75, 76, or 77 is required. These, therefore, have no suffixes appended because they are unique to the left half only. The bladder would not be perforated at this point and would be sealed at the cemented ends. FIG. 3 would therefore depict the bladder as a complete circle.

It will be apparent that as the operating handle 76 is rotated gear 67a meshing with racks 63a and 65a will cause them to move in opposite directions moving rod 64a to the right across the connector interface and re tracting dummy rod 66a further into housing. Through rack 65b attached to rod 66b and pinion 67b the reverse movement is imparted to rack 63b and rod 64b which moves across the connector interface to follow the movement of dummy rod 66a as it retracts into the housing. Since the rods in the left unit abut those in the right unit and transmit motion thereto by pushing their mating rod, no operating handle is required on the right unit.

The previous description was concerned primarily with the mechanical movement of the rods and the mechanism for effecting the seesaw movement. It also described in part the liquid seals, but did not complete that description. The bladder 55a was stated to be cemented to the spine 52a and sealed with a gland as shown in FIG. 4 for passage of the operating shaft. Not described were the sealing means for the ends of the plug.

The rear of the plug after installation and connection of the current carrying wires is encapsulated or potted with a elastomeric compound which seals the cable, the spine 52a, and the housing 50a. This molded seal is designated by 78a and 78b in FIG. 2.

The front end of the plug has a cap 79a which is sealed to the spine 52a and housing 50a and has O-ring seals 80a and 81a which seal the rods against liquid transfer. The caps 79a and 7% are provided with interupted flanges (not shown) such that a shroud ring 82 and resilient washer 83 can be manually rotated to lock the two connector elements together by rotation thereof.

Remaining to be described is the mechanism for effecting electrical connection between the connector halves. For this purpose reference will be made to FIGS. 2, 5A and 58. Each active rod 64a and 6412 has two spaced circumferential contact rings 84a, 85a, 84b and 85b, respectively insulated from one another. By metallic connections within the molded insulation of the rods the band 84a is connected to metallic tab 86a and band 85a connected to the tab 89a (87a duplicated). Corresponding connections are made to the correspondingly numbered b parts in the right unit.

The tab 86a is shaped with an inclined ramp (FIG. 5A) which when the rods are activated coacts with a rocking contact block assembly 900. The block assembly is pivoted on a shaft captivated between spine 52a and end cap 79a, the pivot axis being parallel to the longitudinal axis of the connector. When the rods are transferred across the connector interface the tab 86a ramps or earns the contact block assembly 90a to rock contacts thereon into engagement with bands 84b and 85b. This movement is effected during the final stroke of the rods so as to prevent scrubbing of the rods and transfer of contact material across the insulating gap between the Contact bands.

Resilient contact blades 91a and 92b make electrical contact with contact bands 84b and 8512 respectively when the rods are advanced and contact block assem-- bly 90a rocked into engagement. Block assembly 90b performs a counterpart function to engage contacts 91b and 92b with bands 84a and 85a. Wires 93a and 94a connect the blades 91a and 92a to the power-cable.

By extrapolation of the description of the description of the schematic showing of FIGS. 1A and IE it will be seen that FIG. 5A shows the parts in mating but nonconducting status while FIG. 5B shows the parts conducting. There are four circuits established in the latter condition. If power flows from left to right (purely arbitrary) a pair of circuits flows through wires 87a and 88a to the bands 84a and 85a and to the contact block 90b and associated contacts. A second pair of circuits flows through wires 93a and 94a, contact block 85b and to wires 87b and 8819.

It is to be noted that the rods are normally sealed by their respective O-rings against the entrance of seawater or loss of dielectric fluid. Since the pressures are balanced because of the flexibility of the bladder there is no pressure force to causing fluid migration. When the active rods cross the interface between the mating connector halves they necessarily pass momentarily through a narrow seawater barrier. To avoid contact pollution or corrosion, the seawater is first squeezed by the O-ring as the rod enters the other chamber. This is then followed by a cleansing action which lifts any film of seawater from the rods, since the dielectric fluid wets the surface. Except for this brief exposure to seawater during connect and disconnect operations, the operating parts are protected by the dielectric fluid at all other times.

In the foregoing description an underwater electrical connector has been described in which two housings filled with dielectric fluid are first mated and a physical seesaw transfer of contact rods effected between the two chambers to establish electrical conduction paths between the two chambers without changing the volume of the chambers to produce unbalanced pressures and fluid flow.

As a variation of the same principle it is possible to employ a single chamber with a dummy plug extending through the chamber and exposed at both ends to the sea. When electrical connection is to be made an active plug is attached to the dummy plug and inserted into the housing, pushing the dummy plug through the housing and into the sea. Seals at both openings in the housing, and a filling of dielectric fluid provide the constant volume to prevent entrance of water or loss of dielectric fluid. A diaphragm compensates for minor volume changes.

While this variation exploits the principle of constant volume, it does not provide protection for the active plug when it is unplugged. It does, however, provide the cleansing action for the contacts when they are plugged.

While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that changes in form and details may be made therein without departing from the spirit and scope of the invention.

What is claimed is:

1. An underwater electrical connector comprising:-

a. A first housing filled with a dielectric fluid and having an elastic membrane separating the said fluid from the surrounding water;

b. A first pair of parallel spaced rods journalled for axial movement within said housing;

0. First means for axially moving said rods in equal and opposite directions to extend a portion of one of said rods outside of the housing and to retract the other rod further within the housing;

d. A second housing filled with a dielectric fluid and having an elastic membrane separating the said fluid from the surrounding water;

e. A second pair of parallel spaced rods journalled for axial movement within said housing;

f. A second means for axially moving said rods in equal and opposite directions to extend a portion of one of said rods outside of the housing and to retract the other rod further within the housing;

g. Contact means on each one of the said rods which is extended outside of its respective housing by the movement thereof;

h. Means in each housing for making an electrical connection to the said contact means on the respective rod;

i. Circuit making means in each housing coacting with contacts on the rod from the other housing to effect electrical conduction therewith;

j. And means holding said first and second housings in aligned abutting relationship to permit the rod expelled from said first housing to enter said second housing and the rod expelled from said second housing to enter said first housing, whereby the volume of fluid in each housing remains constant and electrical conductivity between the two housings can be selectively established.

2. The connector of claim 1 wherein fluid seals are provided between each housing and the rods to prevent entrance of water or loss of dielectric fluid.

3. The connector claim 1 wherein said circuit making means within each said housings are normally spaced from the rods but are moved into contact with the rods only during the final stroke of the rods.

4. An underwater electrical connector comprising a. At least one housing enclosing a chamber filled with an inert substantially incompressible dielectric fluid, and having at least two openings therein connecting the said chamber with the water surrounding the said connector when submerged;

b. At least one insulating member within said chamber and mounted for movement in said housing from a first to a second position, the said member having a cross-sectional shape and complementary to said openings, and fitted within both said openings in the said first position of said member to seal said chamber from the surrounding water, and fitted within one only of said openings in the said second position of said member;

c. At least one plug means positioned adjacent said opening and having a cross-sectional shape complementary to at least one of said openings in said housing and operative when manually inserted into one of the openings in said housing to move said insulating member from said first to said second position, and to coact with the complementary opening into which it is inserted to seal said chamber from the surrounding water;

d. Electrical contact means within said housing;

e. Complementary electrical contact means on said plug member, operative when said plug is inserted into said housing to coact with the contacts in the housing to effect electrical connection therewith; whereby when said insulating member occupies said first position said chamber is sealed from the surrounding water by said member, and when said plug is inserted into said housing to effect electrical interconnection, said insulating member is moved from said first to said second position and said chamber is sealed from the surrounding water by the coactionof said insulating member with one of said openings and by the coaction of said plug with the other of said openings and the volume of said chamber remains constant.

5. The connector of claim 4 wherein said movable member is a solid member and said openings are axially aligned, and said plug is a solid member having the same cross-sectional configuration as said member, whereby, when said plug is inserted into said housing it abuts said member and moves the member through said housing and into the surrounding water a distance equal to the movement of said plug into the housing to preserve the constant volume in said chamber.

6. The connector of claim 4 wherein two similar housings, each enclosing a separate chamber, are provided and each has at least one insulating member and one plug member, and means operative upon mating of the two housings for moving the two members within each chamber in equal and opposite directions whereby the plug member from each of the housings is inserted into the other housing to effect electrical connection with the contacts therein while displacing the coacting insulating member within the chamber to maintain a constant volume within both said chambers.

l l l 

1. An underwater electrical connector comprising: a. A first housing filled with a dielectric fluid and having an elastic membrane separating the said fluid from the surrounding water; b. A first pair of parallel spaced rods journalled for axial movement within said housing; c. First means for axially moving said rods in equal and opposite directions to extend a portion Of one of said rods outside of the housing and to retract the other rod further within the housing; d. A second housing filled with a dielectric fluid and having an elastic membrane separating the said fluid from the surrounding water; e. A second pair of parallel spaced rods journalled for axial movement within said housing; f. A second means for axially moving said rods in equal and opposite directions to extend a portion of one of said rods outside of the housing and to retract the other rod further within the housing; g. Contact means on each one of the said rods which is extended outside of its respective housing by the movement thereof; h. Means in each housing for making an electrical connection to the said contact means on the respective rod; i. Circuit making means in each housing coacting with contacts on the rod from the other housing to effect electrical conduction therewith; j. And means holding said first and second housings in aligned abutting relationship to permit the rod expelled from said first housing to enter said second housing and the rod expelled from said second housing to enter said first housing, whereby the volume of fluid in each housing remains constant and electrical conductivity between the two housings can be selectively established.
 2. The connector of claim 1 wherein fluid seals are provided between each housing and the rods to prevent entrance of water or loss of dielectric fluid.
 3. The connector claim 1 wherein said circuit making means within each said housings are normally spaced from the rods but are moved into contact with the rods only during the final stroke of the rods.
 4. An underwater electrical connector comprising a. At least one housing enclosing a chamber filled with an inert substantially incompressible dielectric fluid, and having at least two openings therein connecting the said chamber with the water surrounding the said connector when submerged; b. At least one insulating member within said chamber and mounted for movement in said housing from a first to a second position, the said member having a cross-sectional shape and complementary to said openings, and fitted within both said openings in the said first position of said member to seal said chamber from the surrounding water, and fitted within one only of said openings in the said second position of said member; c. At least one plug means positioned adjacent said opening and having a cross-sectional shape complementary to at least one of said openings in said housing and operative when manually inserted into one of the openings in said housing to move said insulating member from said first to said second position, and to coact with the complementary opening into which it is inserted to seal said chamber from the surrounding water; d. Electrical contact means within said housing; e. Complementary electrical contact means on said plug member, operative when said plug is inserted into said housing to coact with the contacts in the housing to effect electrical connection therewith; whereby when said insulating member occupies said first position said chamber is sealed from the surrounding water by said member, and when said plug is inserted into said housing to effect electrical interconnection, said insulating member is moved from said first to said second position and said chamber is sealed from the surrounding water by the coaction of said insulating member with one of said openings and by the coaction of said plug with the other of said openings and the volume of said chamber remains constant.
 5. The connector of claim 4 wherein said movable member is a solid member and said openings are axially aligned, and said plug is a solid member having the same cross-sectional configuration as said member, whereby, when said plug is inserted into said housing it abuts said member and moves the member through said housing and into the surrounding water a distance equal to the movemeNt of said plug into the housing to preserve the constant volume in said chamber.
 6. The connector of claim 4 wherein two similar housings, each enclosing a separate chamber, are provided and each has at least one insulating member and one plug member, and means operative upon mating of the two housings for moving the two members within each chamber in equal and opposite directions whereby the plug member from each of the housings is inserted into the other housing to effect electrical connection with the contacts therein while displacing the coacting insulating member within the chamber to maintain a constant volume within both said chambers. 